[39.04] Observing with HST IV: New Capabilities with HST in Cycle 6

A. Berman (CSC/STScI), A. Storrs (STScI), W. Workman (CSC/STScI)

Starting in Cycle 6, several new capabilities are available to HST
observers. Some of these capabilities, specified as ``Special
Requirements'' in the Phase II proposal, can be used to allow certain
types of observations to be implemented in a manner which makes more
efficient and flexible use of the HST spacecraft time. This can
translate directly into more useful time on target for the observer.

One of the most innovative new capabilities is called Reuse Target
Offset, which can be used to replace most ``Interactive Acquisitions'' or
to replicate the results of an ``Onboard Acquisition''. Using Reuse
Target Offset in the latter case, for example, obviates the need for
duplicate, time consuming target acquisition exposures in successive
visits observing the same target.

Another new capability is a routine to dither the WFPC2 CCD's
(i.e., repeating the same image at slightly different pointings). This routine
is extremely useful for removing the effects of bad (or ``hot'') pixels when
observing extended sources. It also helps minimize the effects of cosmic rays,
and returns sub-pixel spatial information. This routine is easier to use than
the existing SPATIAL SCAN Special Requirement and requires less time than the
POS TARG Special Requirement.

In this paper, we will present these and all of the other new HST
capabilities with full examples of when each is most useful.